1. Field
The embodiment relates to a method and apparatus to control electric power of a coil which performs induction heating in an imaging apparatus.
2. Description of the Related Art
In general, electrophotographic imaging apparatuses, such as laser printers, facsimile machines, or copiers, form an image in the following manner. An electrical latent image formed on a photoconductive drum is developed with toner into a visible toner image, the visible toner image is transferred onto a printing medium supplied from a paper supply cassette, and the transferred toner image is fixed on the printing medium. In such electrophotographic imaging apparatuses, in most cases, the transferred toner image is fixed by simultaneously applying heat and pressure on the printing medium. Thus, a fixing apparatus to fix the toner image to the printing medium necessarily includes a heating unit to apply heat to the printing medium and a pressing unit to apply a predetermined pressure to the printing medium while in contact with the heating unit. In this case, the heating unit is operated in a lamp-heating manner in which radiation heat of a halogen lamp is used or an induction-heating manner in which heat resistance of an induction coil is used. Between the two, the induction-heating manner is used more often due to its high efficiency. Meanwhile, in order to drive a heating unit in the induction-heating manner, electric power is provided to the heating unit, which includes a coil. However, when power voltage to the coil is too high, damage may result to the heating unit, an inverter to drive the heating unit, inner devices of the imaging apparatus, and an imaging system.